Joint operations, joint education, and joint war planning are nothing new for the Army and Navy, although there are those who apparently lose sight of the fact.
Eaton, George B.
"General Walter Krueger and Joint War Planning, 1922-1938,"
Naval War College Review: Vol. 48:
2, Article 8.
Available at: https://digital-commons.usnwc.edu/nwc-review/vol48/iss2/8